Kafka output
editKafka output
editThe Kafka output sends events to Apache Kafka.
Compatibility: This output can connect to Kafka version 0.8.2.0 and later. Older versions might work as well, but are not supported.
This example configures a Kafka output called kafka-output in the Elastic Agent
elastic-agent.yml file, with settings as described further in:
outputs:
kafka-output:
type: kafka
hosts:
- 'kafka1:9092'
- 'kafka2:9092'
- 'kafka3:9092'
client_id: Elastic
version: 1.0.0
compression: gzip
compression_level: 4
username: <my-kafka-username>
password: <my-kakfa-password>
sasl:
mechanism: SCRAM-SHA-256
partition:
round_robin:
group_events: 1
topic: 'elastic-agent'
headers: []
timeout: 30
broker_timeout: 30
required_acks: 1
ssl:
verification_mode: full
Kafka output configuration settings
editThe kafka output supports the following settings, grouped by category.
Many of these settings have sensible defaults that allow you to run Elastic Agent with
minimal configuration.
| Setting | Description |
|---|---|
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(boolean) Enables or disables the output. If set to |
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The addresses your Elastic Agents will use to connect to one or more Kafka brokers. Following is an example hosts:
- 'localhost:9092'
- 'mykafkahost01:9092'
- 'mykafkahost02:9092'
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Kafka protocol version that Elastic Agent will request when connecting. Defaults to 1.0.0. The protocol version controls the Kafka client features available to Elastic Agent; it does not prevent Elastic Agent from connecting to Kafka versions newer than the protocol version. |
Authentication settings
edit| Setting | Description |
|---|---|
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The username for connecting to Kafka. If username is configured, the password must be configured as well. |
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The password for connecting to Kafka. |
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The SASL mechanism to use when connecting to Kafka. It can be one of:
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When sending data to a secured cluster through the |
Memory queue settings
editThe memory queue keeps all events in memory.
The memory queue waits for the output to acknowledge or drop events. If the queue is full, no new events can be inserted into the memory queue. Only after the signal from the output will the queue free up space for more events to be accepted.
The memory queue is controlled by the parameters flush.min_events and flush.timeout.
flush.min_events gives a limit on the number of events that can be included in a single batch, and
flush.timeout specifies how long the queue should wait to completely fill an event request. If the
output supports a bulk_max_size parameter, the maximum batch size will be the smaller of
bulk_max_size and flush.min_events.
flush.min_events is a legacy parameter, and new configurations should prefer to control batch size
with bulk_max_size. As of 8.13, there is never a performance advantage to limiting batch size with
flush.min_events instead of bulk_max_size.
In synchronous mode, an event request is always filled as soon as events are available, even if
there are not enough events to fill the requested batch. This is useful when latency must be
minimized. To use synchronous mode, set flush.timeout to 0.
For backwards compatibility, synchronous mode can also be activated by setting flush.min_events to 0
or 1. In this case, batch size will be capped at 1/2 the queue capacity.
In asynchronous mode, an event request will wait up to the specified timeout to try and fill the
requested batch completely. If the timeout expires, the queue returns a partial batch with all
available events. To use asynchronous mode, set flush.timeout to a positive duration, for example 5s.
This sample configuration forwards events to the output when there are enough events to fill the
output’s request (usually controlled by bulk_max_size, and limited to at most 512 events by
flush.min_events), or when events have been waiting for
queue.mem.events: 4096 queue.mem.flush.min_events: 512 queue.mem.flush.timeout: 5s
| Setting | Description |
|---|---|
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The number of events the queue can store. This value should be evenly divisible by the smaller of Default: |
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Default: |
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(int) The maximum wait time for Default: |
Topics settings
editUse these options to set the Kafka topic for each Elastic Agent event.
Partition settings
editThe number of partitions created is set automatically by the Kafka broker based on the list of topics. Records are then published to partitions either randomly, in round-robin order, or according to a calculated hash.
In the following example, after each event is published to a partition, the partitioner selects the next partition in round-robin fashion.
partition:
round_robin:
group_events: 1
| Setting | Description |
|---|---|
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Sets the number of events to be published to the same partition, before the partitioner selects a new partition by random. The default value is 1 meaning after each event a new partition is picked randomly. |
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Sets the number of events to be published to the same partition, before the partitioner selects the next partition. The default value is 1 meaning after each event the next partition will be selected. |
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List of fields used to compute the partitioning hash value from. If no field is configured, the events key value will be used. |
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Randomly distribute events if no hash or key value can be computed. |
Header settings
editA header is a key-value pair, and multiple headers can be included with the same key. Only string values are supported. These headers will be included in each produced Kafka message.
| Setting | Description |
|---|---|
|
The key to set in the Kafka header. |
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The value to set in the Kafka header. |
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The configurable ClientID used for logging, debugging, and auditing purposes. The default is |
Other configuration settings
editYou can specify these various other options in the kafka-output section of the agent configuration file.
| Setting | Description |
|---|---|
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(string) The number of seconds to wait before trying to reconnect to Kafka
after a network error. After waiting Default: |
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(string) The maximum number of seconds to wait before attempting to connect to Kafka after a network error. Default: |
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The maximum length of time a Kafka broker waits for the required number of ACKs before timing out (see the Default: |
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(int) Duration to wait before sending bulk Kafka request. Default: |
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(int) The maximum number of events to bulk in a single Kafka request. Default: |
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(int) Per Kafka broker number of messages buffered in output pipeline. Default: |
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Output codec configuration. You can specify either the
Example configuration that uses the output.console:
codec.json:
pretty: true
escape_html: false
Example configurable that uses the output.console:
codec.format:
string: '%{[@timestamp]} %{[message]}'
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Select a compression codec to use. Supported codecs are |
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For the Increasing the compression level reduces the network usage but increases the CPU usage. Default: |
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(string) The keep-alive period for an active network connection. If Default: |
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(int) The maximum permitted size of JSON-encoded messages. Bigger messages will be dropped. This value should be equal to or less than the broker’s Default: |
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Kafka metadata update settings. The metadata contains information about brokers, topics, partition, and active leaders to use for publishing.
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The ACK reliability level required from broker. 0=no response, 1=wait for local commit, -1=wait for all replicas to commit. The default is 1. Note: If set to 0, no ACKs are returned by Kafka. Messages might be lost silently on error. Default: |
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The number of seconds to wait for responses from the Kafka brokers before timing out. The default is 30 (seconds). Default: |